This invention relates to a novel balanced skeletal traction apparatus. More specifically, this invention relates to a balanced skeletal traction apparatus used for aligning fractured leg bones of a patient following surgery or injury.
When a portion of a bone is fractured, it is necessary to position the fractured fragments so that the fragments will successfully align and rejoin to insure resumption of a structural bone member. Reduction, as applied to fractures, refers to the means employed to bring the fracture fragments back into close apposition and alignment. Immobilization, as applied to fractures, refers to the means employed to maintain the reduction until successful repair of the fracture has occurred. In this connection, three principal factors determine, to a large extent, whether the fractured fragments will heal successfully. First, the accuracy of the reduction of the displaced fracture fragments is essential. Second, efficiency of the immobilization by which the fracture fragments are held in the reduced position is important. Third, the local blood supply available to the fracture fragments must be maintained to facilitate proper bone knitting between adjacent fragments.
Insufficient reduction may result in malunion, delayed union, or nonunion of the fracture. All of these maladies complicate and extend the recuperative process. It is therefore highly desirable to promote and facilitate the reduction of and blood supply to the fractured fragments of a leg bone so that the fractured fragments may heal. A successful method of treatment is based first on obtaining reduction and then maintaining reduction until fracture healing occurs in a bone while concurrently encouraging an adequate blood supply to the injured area. A common means of both obtaining and maintaining reduction is through the use of traction devices.
Traction has been used to treat fractures for hundreds of years and is still the most commonly indicated method of treatment. Traction is classified as being applied through either skin or bone, and may be further classified by the direction of the traction (i.e. horizontal, vertical, or oblique). In practice, traction is exerted on the distal fracture fragment, aligning it with the less manageable proximal fragment.
Horizontal skin traction was first applied in the 14th century for the treatment of femoral fractures. A method commonly used in the past was introduced during the American Civil War. Named Buck's traction after its inventor, this type of simple traction aligns femoral fracture fragments in a horizontal direction. A patient lying in a supine position has strips of ordinary adhesive tape applied to the sides of the leg and attached to a spreader block at the foot. The leg is wrapped with an elastic bandage to improve purchase of the tape on the skin. A piece of traction cord attaches the spreader block to a weight, which is hung over the foot of a bed. The lower leg is supported on a pillow to reduce friction of the heel against the bed linen. Countertraction is supplied by elevating the foot of the bed on shock blocks. A disadvantage of this type of traction is that supporting the lower leg on a pillow invites unintentional patient rotation of the lower leg and corresponding complications connected with disturbance of the fracture fragments during the healing process.
Vertical skin traction has been popular since being introduced in the 1870s. Its popularity is based on the effectiveness of maintaining fracture alignment and the fact that it especially facilitates care of an infant or child in bed. An early vertical skin traction configuration included tape which secured a spreader block to the lower leg, as described above. The leg was vertically attached to a suspension means, thereby aligning the fracture fragments.
Many disadvantages were associated with this configuration. Reduction of blood flow and associated circulation impairment tended to occur in the normal as well as the fractured limb. If a patient moved toward the foot of the bed, hyperextension of the knee further jeopardized limb circulation. Moreover, the circumferential wraps required to hold the traction tapes in place added to the problem of circulation impairment. This device for vertical traction was improved by lowering the inclination of the leg to about 45 degrees, versus 90 degrees, thus reducing the risk of vascular compromise. However, problems of the type previously described still remained.
Oblique skin traction has been commonly used in several forms, employing various means of supporting the leg, and producing a resultant traction. In the past the weight of the fracture fragments was supported by a sling to prevent posterior angulation. Russell's method for oblique skin traction was introduced in 1921 and is often employed by attending physicians. This method is used for children and adults and provides a single traction system for both vertical and horizontal traction by means of a sling beneath the proximal leg or knee and longitudinal traction along the distal portion of the leg, respectively. A traction doubling pulley system was particularly applicable to adults who required substantial longitudinal traction to prevent shortening of the healing bone.
Russell's method of skin traction limited versatility by attaching both the vertical and horizontal traction means to a single pulley. An improvement over this configuration was realized when the vertical support sling and the distal traction elements were separated with independent pulleys and weights. This system provided greater flexibility.
In this improved traction device, the force counteracting the fracture fragments is the resultant force of the vertical sling and the horizontal traction along the leg. For this reason it is important that the vertical sling be under the proximal leg rather than under the thigh. If the sling is placed under the thigh, the force is directed more cephalad with less resultant force. This cephalad force can also cause anterior angulation to occur at the fracture site. The vertical sling must be at least 90 degrees or slightly caudal to the horizontal pull along the leg to achieve an adequate resultant force. A second force, the pull of gravity, can produce posterior bowing at the fracture site. In order to counter this force, a pillow was placed under the thigh to prevent the posterior bowing.
Problems associated with the previously described system include difficulties involved in assembling such a complex system of pulleys. Multiple medical personnel are needed to accurately align and reduce the fractured fragments. It is also difficult to make adjustments to the direction of traction or the traction force because of the interaction between the pulleys. Further, a patient's movement is almost completely restricted and therefore tends to make recuperation an uncomfortable process.
The difficulties suggested in the preceeding are not intended to be exhaustive but rather are among many which may tend to reduce the effectiveness and physician satisfaction with prior balanced skin traction devices. Other noteworthy problems may also exist; however, those presented above should be sufficient to demonstrate that balanced skeletal traction devices appearing in the past will admit to worthwhile improvement.